Noiseless pawl and ratchet mechaniem



H. F. E. BAESELER.

NOIS'ELESS PAWL AND RATGHET MECHANISM.

APPLICATION FILED OCT. 12, I920.

1,409,814. Patel lted Mar- 14, 2.

2 SHEETSSHE flyeizi a?" ZBaedeZerwmveey H. F. E. BAESELER.

' NOISELESS PAWL AND RATCHET MECHANISM.

APPLICATION FILED OCT. 12. 1920.

1,409,814. Patented Mar. 14, 1922.

2 SHEETSSHEET 2.

Worll 84,274, France April 16 UNITED STATES- PATENT orncs.

HEINBIOH FRANZ EDMUND 3mm 01' DMDH QW, AISIGIOB 1'0 ART.

one. vomr snrnm. a munumr, or 11mm, 0mm, 4 comm-non or norsnnsss rawr. um amoun- 1,4oe,s14.

. specincation of Letters Patent. Patentedfiiir, 14, 1922- Appllcatlon filed October 12, 1980. lerlallc: 418,571

(GRANTED man 'IHIPBOVISIOIS Q! m A0! ormcn 8,1981, ISA-T. 1., 1818.)

To all whom it may concern:

Be it known that I, Hnmnrcn Fnaxz En- MUND BAESELER, a citizen of the German Regpblic, residing at Dresden, Germany,

humannstr. 24, have invented certain new and useful Im rovements in a Noiseless Pawl and Ratchet lllechanism, (for which I have filed applications in Germany July 12, 1918, Austria Mar. 28, 1919,Hungar Mar. 29, 1919, Switzerland June 30, 1919 Patent No. 1919, ltaly May 9, 1919, and Sweden April the following is a specification.

My present invention relates to noiseless paw and ratchet mechanism and has for its object to provide a device in which a ratchet is operated in the ordinary manner in one direction by a pawl, means being provided to release said pawl from the ratchet teeth when said ratchet is moved in the opposite direction in order to avoid theclicking noise made by the pawl sliding idly over the ratchet teeth.

In the preferred embodiment of the invention, the ratchet is used as the ordinary escapement wheel of a typewriting machine. b means of which the carriage is moved a ong to space the letters, and it is on the return movement of said carriage to initial position that the release of said pawl from said escapement wheel is brought about permitting a noiseless return of said carriage.

In the drawings y Figure '1 is an elevational view of one embodiment of my invention showing the pawl in engagement with the escapement wheel.

I:ti1gure 2 is a plan view 0 Figure 1 taken pa y in section.

Figure 3 is a view similar to Figure 1 showing the pawl-released from engagement with the escapement wheel. g

4, 5 and 6 are'views similar respectlvely to Figures 1 2 and- 3 but showin a modified form of-lh invention;

igures 7 and 8 are etails of the pawl and ratchet mechanism shown in Figures 4 and 6. r

In the drawings A represents the-escape-. ment support of a typewriting machine having journalled therein the shaft B mounted upon one end of which is a gear wheel 5 engaging the rack bar 6' by means of which the carriage is moved along in a left to 2, 1919,) of which 7 escapement .dog

purpose of spacing prior to the release of the'escapement w eel from engagement with the pawl 1'. The 3' is provided with anarm 4 carrying a pln'O and ada ted to engage an arm D project-in from the pawl 1. A stop 10 is supporte \by the carriage in the path of the pawl 1 to limit the extent'of its movement in a release direction.

The escapement d an arm E to which is'attached the link F for operating the mechanism.

When the link F is pulled by means of a key not shown, the escapement dog moves between adjacent teeth of the escapement wheel and the pin C carried by said dog then strikes the arm D of the pawl 1 throwing it out of engagement with the teeth of the escapement wheel and permittin it to advance the space of onetooth. if sp G constantly impels the pawl into the path of the escapement teeth- Rotatably mounted upon the shaft B is-the auxiliary ratchet 7 pressed into frictional engagement with the escapement wheel 2 by means of a spring washer 8 best shown in Figure 2. r

The frictional hold of said au'xilia ratchet with the escapement wheel 2 is m cient to carry saidzauxiliary ratchet with said escapement wheel as the latter moves in the direction of the arrow and also when 3 is provided with of the pawl 9.

Thus the pawl 1 will be held out of contact with the teeth of the escapement wheel during the entire reverse movement of the carriage.

In the form of execution illustrated in Figures 4 to 8 thedog 13 which temporarily locks the escapement wheel 12 and the auxiliary pawl 21 are arranged upon the same shaft 22 upon which the pawl 19 is mounted. The auxiliary pawl 21 engages the ratchet wheel 11 which is pressed by the spring disk 14 against the escapement wheel 12. A spring 15 is interposed between the pawl 19 and the auxiliary pawl'2l, the pawl 19 being acted upon by a spring 16. A stop 17 is provided on the dog 13 said stop being adapted to engage the pawl 19. Figures 7 and 8 show the arrangement of the operating mechanism the auxiliary pawl being omitted, Figure 7 showing the inoperative position and Figure 8 the operative position of the .parts. By oscillating the dog 13 into a tooth gap of the escapement wheel, the pawl 19 is temporarily released sothat the escapement wheel can be advanced in a manner similar to that described under the modification shown in Figure 1.

In the construction shown in Figures 4 to 8 the auxiliary pawl 21 ermits an unimpeded advancing rotation of tile escapement wheel in the direction of the arrow shown in Figure 4:. While during the return rotation as shown in Figure 6 the ratchet wheel 11 acts to turn the pawl in such a manner that the latter carries with it the pawl 19 by means of the stop 20 so far that said pawl i '19 strikes against the stop 23 and accord- 45 ingly remains released during the entire continuance of the return movement.

Having thus particularly described the nature of my. invention what I claim as new and desire to secure by Letters Patent of the United States is 1. In a noiseless paWl and ratchet mechanism, in combination an escapement wheel, a main pawl adapted to temporarily release the escapement wheel and thereby permit an advancing movement of said wheel, an auxiliary pawl connected to the main pawl and a ratchet wheel constructed to be carried along frictionally by said escapement wheel in one direction and to act when moving in the other direction'uponsaid auxiliary pawl the latter serving when acted upon to lift the mainv pawl out of engagement with the escapement wheel. 4 I v 2. Ina noiseless pawl and ratchet mechanism, a shaft, an escapement wheel fixed to said shaft, a ratchet wheel rotatably mounted on said shaft, means for holding said ratchet while normally in frictional engagement with said escapement wheel to rotate therewith, a pivoted main pawl engaging said escapement wheel, an auxiliary pawl engageable with said main pawl and said ratchet wheel, means for releasing said pawl to permit movement/of said escapement wheelv in one direction, said escapement wheel when moving in the other direction carrying said ratchet wheel into contact with said auxiliary pawl to push the main pawl to-released position, and a stop engaging said main pawl and acting through said auxiliary pawl to inhibit the rotation of said ratchet wheel, further reverse rotation of said escapement wheel being possible through slippage between the frictional contacting surface of said escapement wheel and ratchet.

3. A noiseless pawl and ratchet mechanism comprising a shaft, an escapement wheel fixed to said shaft, a ratchet wheel rotatably mounted on said shaft and adjacent said escapement wheel, means for holding said ratchet wheel in frictional engagement with said escapement wheel, a main pawl enga cable with said escapement wheel for contro ling the movement thereof in one direction, an a'uxiliar pawl associated with said main pawl an engageable by said ratchet wheel to release said auxiliary pawl on reverse movement of said escapement wheel, a stop to limit the movement of said main pawl and ratchet wheel, further movement of the escapement being permitted through slippage between said escapement tween said ratchet wheel and escapement.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

HEINRICH FRANZ EDMUND BAESELER.

Witnesses:

HEINRICH GEI-NLER, -WILHELM BLEIHEN. 

